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Close to the edge: hierarchy in a double braneworld

Rommel Guerrero·Alejandra Melfo·Nelson Pantoja·R. Omar Rodriguez
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Abstract

We show that the hierarchy between the Planck and the weak scales can follow from the tendency of gravitons and fermions to localize at different edges of a thick double wall embedded in an $AdS_5$ spacetime without reflection symmetry. This double wall is a stable BPS thick-wall solution with two sub-walls located at its edges; fermions are coupled to the scalar field through Yukawa interactions, but the the lack of reflection symmetry forces them to be localized in one of the sub-walls. We show that the graviton zero-mode wavefunction is suppressed in the fermion edge by an exponential function of the distance between the sub-walls, and that the massive modes decouple so that Newtonian gravity is recuperated.

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Rommel Guerrero, Alejandra Melfo, Nelson Pantoja, R. Omar Rodriguez. 2006-06-14. Close to the edge: hierarchy in a double braneworld. https://doi.org/10.1103/physrevd.74.084025

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